1. Field of the Invention
This invention relates to an electric connector for connecting as coaxial ribbon cable.
2. Description of the Prior Art
Recently, the propagation speeds of integrated circuits used in computer circuit systems have become higher and higher. Therefore, in transmitting a signal between circuit boards or assemblies, coaxial cables have been more frequently used for the purpose of minimizing incoming noises or crosstalks. Heretofore, connection of such a coaxial cable to a circuit board was effected by individually soldering the center conductor and the ground conductor of the coaxial cable to the corresponding terminals fixed to the circuit board. This was a time-consuming and costly operation. However, in order to avoid such an operation, an expensive coaxial connector must have been used. On the other hand, recently, as a countermeasure to high density package due to increase in the number of signals appearing in circuit systems, a coaxial ribbon cable has been developed for use in interconnecting the circuit systems. One type coaxial ribbon cable comprises a common outer jacket and a plurality of coaxial cables arranged in parallel to one another within the jacket. Another type coaxial ribbon cable comprises a plurality of single coaxial cables adhered together parallel to one another. Each of the coaxial cables has a center conductor for transmitting high speed pulse signals, an outer conductor for shielding the center conductor against external interferences and a dielectric for isolating the center conductor from the outer conductor. The outer conductor may be in the form of a woven metallic wire or a coiled metallic wire or a metallic foil surrounding the dielectric. Electric connectors for connecting such a coaxial ribbon cable have been proposed and used. However, these connectors have the disadvantages that their packaging density is low, they can be used only for certain coaxial ribbon cables, they are not suitable for connecting a small coaxial ribbon cable, they are not economical because the same number of ground terminals as there are signals is required and the high speed transmitting characteristics in the connecting part are unsatisfactory. Moreover, according to a given frequency and noise margin, it is often necessary to selectively change the arranged pattern of ground terminals. However, in the conventional electric connectors, it was difficult to realize such a change of ground pattern.
Therefore, it is an object of this invention to eliminate the above disadvantages and provide an electric connector for coaxial ribbon cable wherein a high density packaging can be realized and the change of ground pattern can be easily effected.